Limit stop for electric hoists



F. H. HOWARD LIMIT STOP FOR ELECTRIC HOISTS Oct. 27 1925- 1,559,102

Filed Feb. 14, 19,25

J-zy/ STA'I'ES rATEN'r orrics.

FRANK I-I. HOWARD, 0F READING, PENNSYLVANIA, ASSIGNOR TC READING CHAIN AND BLOCK GORPORATIGN, OF READING, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

LIIYIIT STOP FOR ELECTRIC HOISTS.

Application filed February To all whom it may concern: c

lie it known that I, FRANK H. HOWARD, a citizen of the United States, residing at Reading, in the county of Berks and State of i ennsylvania, have invented certain new. and useful improvements in Limit Stops for Electric L'oists, which the following is a specification.

T his invention relates to a limit stop for electric hoists and the object is to provide simple and effective device whereby the controller may e actuated auton'iatically through the medium of for determining predeterininedly the points at which the controller is to be affected to start or stop the device.

The invention in the present instance consists of a crank mounted on the frame of the winding drum, and interposed between the operating rod leading to the controller, a, d the movable member on the shaft of the winding drum, whereby the actuation t is red is effected.

The invention is more fully described in the accompanying drawing and clearly illustrated in the accompanying drawing. in 3h ich Figure l is a plan view of a portion of a winding drum and its shaft, with my invention applied thereto 7 Figure 2 is a front elevation thereof.

The numeral 1 designates the winding C um of a hoist and this is provided with a screw shaft 2 and on this shaft I place a nut 3, adapted to move when the shaft ro- T his nut is formed with an upstanding pin 4: which engages an elongated slot in one-end of a crank 6, mounted in a casing 7 on the frame of the machine and its lower extremity 9 is in engagement with and adapted to move freely rod having means his crank 6 14, 1925. Serial No. 9,100. 1

on, the end of a controller rod 11. This rod is provided with two movable members 12, capable of adjustment thereon, and contact with either of these members by the end of 40 the crank member 9 will actuate the said rod, which is in engagement at its opposite end with the controller 15.

When the winding drum rotates, the nut 3 moves thereon, until the crank am has moved sufficiently to engage one of the ad justable members 12, and the controller is then actuated.

The construction is extremely simple and its effectiveness is assured by said simplicity. Having thus described the invention, I

claim:

1. In a limit stop for electric hoists, the combination of a controller, a controller rod connected thereto, a winding drum, a screw 60 threaded shaft for the drum, a nut on said shaft adapted to be moved by the rotation of the shaft, a pin on said nut, crank having an elongated slot which ages said pin and whose opposite end loosely engages the o5 controlier rod, and means in the form of ad just-able nuts on said rod to determine the point at which the rod will be moved by the crank.

2. In a limit stop for electric hoists, the combination of a hoisting drum, a controller,

a controller rod connected thereto, a screwthre'aded shaft for the drum, a nut on said shaft, a crank arm mounted on the drum frame, one end of which is inengagement with said nut and the other with said controller rod, and adjustable means on the con j troller rod whereby the time of actuating the controller may be determined.

In testimony whereof I affix my signature.

FRANK H. HOWARD. 

